This proposal intends to develop synthetic receptors for studies of molecular recognition, transport and catalysis. The receptors are deep cavitands, molecules that more or less surround their targets and present reactive functional groups to them. Both organic and water-soluble versions are available to study molecular behavior in small spaces and asymmetric nanoenvironments while they are isolated from bulk solvents. The proposal pursues themes of single molecule spectroscopy, of nanoscience and self-assembly. These are the most advanced synthetic analogs of receptors or enzymes that are available and can provide some keys to fathom their extraordinary reactivity and selectivity. The longer-term objectives are transport across membranes and catalysis involving structures of biologically significance. Specific targets include the reactions of choline and trimethyllysine derivatives. Acetylcholine is a major determinant of cognitive performance and of muscle contraction, and in Alzheimer's disease, a large drop of acetylcholine levels is found in several brain regions. Deep cavitands that can carry choline across the blood brain barrier and the neuronal membrane can be of use in upregulating and restoring acetylcholine levels in disease afflicted brains. Gene activation or repression in higher organisms is controlled by modification of histone proteins. These cavitands could allow the identification of genes whose expression is influenced by trimethylation of particular lysines of the histones.